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The indenyl molybdenum carbonyl complexes [IndMo(CO)2(L)n]BF4 (L = NCMe with n = 3 (1), 2,2′-bipyridine (2) or 1,4,7-trimethyltriazacyclononane (3) with n = 1) promote epoxide alcoholysis under moderate reaction conditions. Complexes 1 and 2 showed the best performance for the alcoholysis of styrene oxide with different alcohol nucleophiles (acting as both reactant and solvent), leading to the corresponding 2-alkoxy-2-phenylethanol with 100% yield at 10 min and 35 °C. These catalytic results are far superior to those found for previously studied molybdenum carbonyl complexes. An efficient procedure for catalyst recovery and reuse without decrease in reaction rate is described.

The cyclopentadienyl molybdenum carbonyl complexes [( η 5 -C 5 H 4 R)Mo(CO) 2 ( η 3 -C 3 H 5 )] and [( η 5 -C 5 H 5 )Mo(CO) 3 (CH 2 R)] (R = H, COOH) have been shown to promote acid-catalysed reactions in liquid phase, under moderate conditions. The catalytic alcoholysis of styrene oxide with ethanol at 35 °C gave 2-ethoxy-2-phenylethanol in 100% yield within 30 min for the dicarbonyl complexes and 3–6 h for the tricarbonyl complexes. Steady catalytic performances were observed in consecutive runs with the same catalytic solution, suggesting fairly good catalytic stability. In the second acid-catalysed reaction studied, the isomerization of α-pinene oxide at 55 °C gave campholenic aldehyde and trans -carveol in a total yield of up to 86% at 100% conversion. Chemoselectivity is shown to be solvent dependent.

Ferrocenium ions, [Fc](+), have been immobilised in the microporous titanosilicate ETS-10 by ion exchange of Na+/K+ ions under hydrothermal conditions. The resultant hybrid inorganic-organometallic (ETS-10/[Fc](+)) material was characterised by elemental analysis, diffuse reflectance UV-Vis spectroscopy, FT-IR spectroscopy, powder X-ray diffraction, scanning electron microscopy, and thermogravimetric analysis. The ETS-10/[Fc](+) sample was tested as a catalyst for the isomerisation of alpha-pinene oxide (PinOx) at 35 degrees C. With alpha,alpha,alpha-trifluorotoluene (TFT) as solvent, campholenic aldehyde (CPA) was the main product formed in 38% yield at 100% conversion and 30 min reaction. Other reaction products included trans-carveol, iso-pinocamphone and trans-pinocarveol. The same PinOx conversion and CPA yield could be reached within 1 min reaction time by increasing the reaction temperature (to 55 degrees C) and the Fe:PinOx molar ratio. Other solvents (hexane, CH3CN, toluene) led to poorer results than TFT. Characterisation of the used catalyst, together with an analysis of the catalytic activity of the liquid phase obtained after contact of ETS-10/[Fc](+) with TFT, indicated that the ETS-10/[Fc](+) sample was resistant toward leaching of iron-containing active species. When the recovered solid was reused in a second batch run, catalytic activity was lower than in the first run, while selectivity to CPA was higher. (C) 2015 Elsevier B.V. All rights reserved.

The ligand N -(n-propyl)-2-pyridylmethanimine (pyim) and an immobilised analogue of this ligand (MCM-41-pyim) were prepared by the condensation reaction of 2-pyridinecarboxaldehyde with either propylamine or aminopropyl groups covalently attached to the ordered mesoporous silica MCM-41. Free and immobilised tetracarbonyl complexes of the type cis -[Mo(CO) 4 (L)] ( L = pyim ( 1 ), MCM-41-pyim) were then prepared by microwave-assisted heating of a mixture of Mo(CO) 6 and the organic ligand or ligand-silica in toluene at 110 °C for 30–45 min. The products were characterised by NMR spectroscopy ( 1 H, 13 C and 29 Si, in solution and in the solid state), elemental analysis, N 2 adsorption, and FT-IR spectroscopy. When used as catalyst precursors for the epoxidation of cis -cyclooctene by tert -butylhydroperoxide at 55 °C (1 mol% catalyst (Mo), no additional co-solvent), 1,2-epoxy-cyclooctane was obtained as the only reaction product in quantitative yield after 5 h for 1 and 36% yield after 24 h for the supported complex. The use of the ionic liquid (IL) 1-butyl-3-methylimidazolium tetrafluoroborate as co-solvent led to lower catalytic activities (epoxide selectivity was always 100%) but allowed the catalyst/IL mixtures (homogeneous mixture for IL+ 1 and a biphasic solid + IL system for IL+MCM-41-pyim/Mo) to be easily recovered and reused in subsequent runs without loss of catalytic performance.